High-sensitive 2nd generation thyroglobulin immunoradiometric assay. Clinical application in differentiated thyroid cancer management.

BACKGROUND: Circulating human thyroglobulin (hTG) measurements have a pivotal role in the management of patients affected by differentiated thyroid cancer (DTC). The present study was undertaken by employing a new developed high-sensitive hTG immunoradiometric assay to evaluate its diagnostic performance in patients affected by radically cured and relapsing DTC and to set the most appropriate cut-off point for DTC management. METHODS: We retrospectively selected 172 patients without signs of recurrence after primary treatment and 45 patients with recurrences from DTC. Serum samples were collected during l-thyroxine (T4) suppressive therapy (onT4) and 4 weeks after T4 withdrawal (offT4) and hTG measured by a specific high-sensitive IRMA assay (DYNOtest Tg-plus, BRAHMS Diagnostica GmbH, Berlin, Germany). Sera showing the presence of AbhTG or hTG-recovery less than 80% were excluded from the study. ROC curve analysis was performed to select the best cut-off levels and diagnostic performance of the marker evaluated. RESULTS: By using onT4 cut-off level of 0.2 ng/mL and offT4 cut-off level of 0.5 ng/mL we obtained a sensitivity/specificity/accuracy profile of 0.91/0.98/0.96 and 0.98/0.97/0.97, respectively. We found onT4-hTG false-negative results in 4 patient with local recurrence (n=2) or cervical lymph-node metastasis (n=2) while only 1 patient with local recurrence showed negative offT4-hTG. However, onT4 and offT4-hTG false-negative results were observed in 9 and 5 patients when 1.0 ng/mL cut-off level was employed. CONCLUSIONS: On the basis of our data, we conclude that DYNOtest Tg-plus assay is very effective and accurate in the evaluation of patients with DTC.

Evaluation of the 2nd generation radio-receptional assay for anti-TSH receptor antibodies (TRAb) in autoimmune thyroid diseases. Comparison with 1st generation and anti-thyroperoxidase antibodies (AbTPO).

BACKGROUND: The detection of autoantibodies to the TSH-receptor (TRAb) by radio-receptor assays (RRA) is widely requested in clinical practice for the diagnostic workup of Graves' disease and its differentiation from diffuse thyroid autonomy. Additionally, TRAb measurement can be useful during antithyroid drug treatment of Graves' disease to evaluate the risk of relapse after therapy discontinuation. Nevertheless, some patients affected by Graves' disease are TRAb-negative when 1st generation assay is used. METHODS: In this study we evaluated the diagnostic performance of a newly developed 2nd generation TRAb assay (TRAK human DYNOtest, BRAHMS Diagnostica GmbH, Berlin, Germany) in 74 untreated patients affected by Graves' disease, 53 untreated patients affected by Hashimoto's thyroiditis and 88 patients affected by euthyroid nodular goiter. We also compared the new TRAb assay with the 1st generation test (TRAK Assay, BRAHMS Diagnostica GmbH, Berlin, Germany) and anti-thyroperoxidase assay (AbTPO DYNOtest, BRAHMS Diagnostica GmbH, Berlin). RESULTS: The 2nd generation TRAb assay showed the better diagnostic sensitivity in Graves' disease (97%) with respect to the 1st generation assay (85%) and AbTPO assay (64%). The AbTPO assay was positive in 50 of 53 (94%) patients affected by autoimmune thyroiditis. The 1st and 2nd generation TRAb assays were positive in 4 (7%) and 7 (13%) of 53 patients affected by autoimmune thyroiditis, respectively. No patients affected by nodular goiter showed positive 1st and 2nd generation TRAb assay while AbTPO levels were positive in 8 of 88 patients (specificity 91%). CONCLUSIONS: In conclusion, the 2nd generation TRAb assay is clearly more sensitive than the 1st generation test and should be used in clinical practice to minimize the incidence of TRAb-negative Graves' disease. Long term prospective studies are needed to evaluate the prognostic role of 2nd generation TRAb assay in Graves' disease. The assay of AbTPO is the best marker for autoimmune thyroiditis but is clearly less sensitive than 1st and 2nd generation TRAb assays in Graves' disease. Consequently, AbTPO assay should not be performed in Graves' disease neither alone or in association with TRAb.

Immunoradiometric assay of chromogranin A in the diagnosis of small cell lung cancer: comparative evaluation with neuron-specific enolase.

The aims of our work were 1) to determine the diagnostic performance of an immunoradiometric assay of chromogranin A (CgA) in small cell lung cancer and 2) to compare its discriminatory power with that of neuron-specific enolase (NSE), the marker currently used for SCLC. We selected 166 cases of small cell (64) and non-small cell (102) lung cancer and 106 cases of non-malignant lung diseases as controls. Both CgA and NSE were assayed by immunoradiometric methods and cutoff values were established on the basis of a pre-fixed specificity of 95% in non-malignant lung diseases. The CgA assay showed better diagnostic sensitivity than NSE in SCLC (61% versus 57%), especially in limited disease, and a low positivity rate in NSCLC with respect to NSE (14% versus 22%). By contrast, NSE reflected disease extent more accurately than CgA (U test: CgA p<0.05, NSE p<0.001). Finally, we found that the CgA assay was not affected by hemolysis whereas NSE serum levels greatly increased in hemolyzed sera. In conclusion, CgA assaying by an IRMA method is a reliable procedure in the diagnosis of SCLC. NSE remains the marker of choice in staging and monitoring of the disease. Further studies are needed to evaluate the prognostic significance of the marker and its role in therapy monitoring and patient follow-up.

Clinical applications of the 2nd generation assay for anti-TSH receptor antibodies in Graves' disease. Evaluation in patients with negative 1st generation test.

Detection of autoantibodies to the thyrotropin receptor by radioreceptor assays is largely requested in clinical practice for the diagnosis of Graves' disease and its differentiation from diffuse thyroid autonomy. Additionally, thyrotropin receptor antibodies (TRAb) measurement during antithyroid drug treatment can be useful to evaluate the risk of relapse after discontinuation of the therapy. Nevertheless, some patients affected by Graves' disease are TRAb-negative when a 1st generation assay is used. In this study we evaluated the diagnostic performance of a newly developed 2nd generation TRAb assay in 46 patients with Graves' disease with negative 1st generation TRAb assay results. A control group of 50 Graves' disease patients with positive 1st generation TRAb assay results, 50 patients with Hashimoto's thyroiditis and 50 patients with nodular goiter were also examined. Forty one of 46 patients with Graves' disease with negative 1st generation TRAb assay results showed a positive 2nd generation test. No differences were seen in control groups. In conclusion, the 2nd generation TRAb assay is more sensitive than the 1st generation test and should be used in clinical practice. Long-term prospective studies are needed to evaluate the prognostic role of the 2nd generation TRAb assay in Graves' disease.

Evaluation of chromogranin A expression in serum and tissues of breast cancer patients.

Human chromogranin A (CgA) is a member of the granin family and is widely distributed in large dense core granules of endocrine and neuroendocrine cells. A variety of non-neuroendocrine carcinomas arising in various tissues show patterns of neuroendocrine differentiation. Expression of CgA has been documented in epithelial cells of normal mammary gland as well as in breast cancers, and elevation of serum CgA has been detected in patients with breast cancer. Our study was undertaken to evaluate the relationship between serum CgA levels and neuroendocrine features in breast cancer. In addition, we evaluated the expression of serum CgA in patients affected by breast cancer compared to controls and the relationship between serum CgA and tumor histology, extent of disease, lymph node status, tumor stage and serum CA 15.3 levels. We enrolled 266 patients with infiltrating ductal or lobular breast carcinoma and a group of 100 age-matched healthy women serving as controls. Serum CgA and CA 15.3 were assayed by specific immunoradiometric methods. The overall sensitivity of CgA and CA 15.3 was 0.06 and 0.34, respectively (chi2 19.1, p<0.0005). No relationship was found between serum levels of CgA and tumor histology, extent of disease, lymph node status or tumor stage while serum levels of CA 15.3 were strongly correlated with all these variables but tumor histology. No relationship was found between serum levels of CgA and CA 15.3. Immunostaining against CgA, CgB, NSE and synaptophysin was performed on primary tumor tissue of 14 serum CgA-positive and 24 serum CgA-negative patients and was negative in all cases. We also evaluated eight cases of pathologically-proven neuroendocrine breast cancer: only four and two of these showed positive CgA immunostaining and increased serum CgA concentration, respectively. In conclusion, serum CgA assay offers no additional information regarding the presence, the extent and the histology of breast cancer compared to the CA 15.3 assay. Moreover, serum CgA was not an accurate marker to identify or exclude the rare neuroendocrine differentiation of breast cancer. We therefore conclude that CgA is not useful as a serum marker in breast cancer.

Late blood pool images after Tc-99m tetrofosmin injection in a patient with monoclonal gammopathy of uncertain significance and immunologic disorders.

The authors report a case of abnormal biodistribution of Tc-99m tetrofosmin in a patient with immunologic disorders who underwent rest-stress myocardial perfusion scintigraphy to assess the operative risk for surgery of possible relapse of adenocarcinoma of the left maxillary sinus. The patient had monoclonal gammopathy of uncertain significance with a serum electrophoretic pattern of both monoclonal immunoglobulin A and free kappa light chain components and a mild form of idiopathic immunohemolytic anemia. Two different images at rest after injection of Tc-99m tetrofosmin showed a typical blood-pool pattern with absence of detectable myocardial uptake. Other patients injected with the same batch of radiopharmaceutical showed myocardial uptake. A change of the molecular characteristics of tetrofosmin after the injection could not be a factor, because the values of the main chemical and physical parameters of the blood were in the normal range. Accordingly, the authors propose the hypothesis that the monoclonal immunoglobulin A or the free kappa light chains of this patient accidentally recognized one or more epitopes of the tetrofosmin molecule, binding it with high affinity and causing an abnormal biodistribution, characterized by late blood-pool imaging. No similar experiences have been described in the scientific literature.

[Radioiodine treatment of hyperthyroidism using a simplified dosimetric approach. Clinical results]. / Terapia radiometabolica dell'ipertiroidismo con approccio dosimetrico semplificato. Risultati clinici.

PURPOSE: To evaluate the clinical effectiveness of a simplified dosimetric approach to the iodine-131 treatment of hyperthyroidism due to Graves' disease or uninodular and multinodular toxic goiter. MATERIAL AND METHODS: We enrolled 189 patients with biochemically confirmed hyperthyroidism and performed thyroid ultrasonography and scintigraphy obtaining the diagnosis of Graves' disease in 43 patients, uninodular toxic goiter in 57 patients and multinodular toxic goiter in 89 patients. In 28 patients we found cold thyroid nodules and performed fine-needle aspiration with negative cytology for thyroid malignancy in all cases. Antithyroid drugs were stopped 5 days till radioiodine administration and, if necessary, restored 15 days after the treatment. Radioiodine uptake test was performed in all patients and therapeutic activity calculated to obtain a minimal activity of 185 MBq in the thyroid 24 hours after administration. The minimal activity was adjusted based on clinical, biochemical and imaging data to obtain a maximal activity of 370 MBq after 24 hours. RESULTS: Biochemical and clinical tests were scheduled at 3 and 12 months posttreatment and thyroxine treatment was started when hypothyroidism occurred. In Graves' disease patients a mean activity of 370 MBq (distribution 259-555 MBq) was administered. Three months after treatment and at least 15 days after methimazole discontinuation 32 of 43 (74%) patients were hypothyroid, 5 of 43 (11%) euthyroid and 6 of 43 (15%) hyperthyroid. Three of the latter were immediately submitted to a new radioiodine administration while 32 hypothyroid patients received thyroxine treatment. One year after the radioiodine treatment no patient had hyperthyroidism; 38 of 43 (89%) were on a replacement treatment while 5 (11%) remained euthyroid. In uni- and multinodular toxic goiter a mean activity of 444 MBq (distribution 259-555 MBq) was administered. Three months posttreatment 134 of 146 (92%) patients were euthyroid and 12 of 146 (8%) patients hyperthyroid. Two patients were immediately submitted to a new radioiodine administration. One year posttreatment 142 of 146 (97%) patients were euthyroid while only 4 of 146 (3%) patients showed TSH levels above the normal range. Only 2 of them required thyroxine treatment. CONCLUSIONS: The simplified dosimetric method illustrated in our paper is very effective in clinical practice because it permits to avoid resorting to sophisticated but also imprecise quantitative methods. Hypothyroidism should not be considered as a major collateral effect of radioiodine treatment, particularly in Graves' disease. In fact, the pathogenesis of the disease requires an ablative treatment with both surgery and radioidine treatment and the control of hyperthyroidism and the prevention of relapse are the major clinical targets. Vice versa, hypothyroidism was very uncommon in uni- and multinodular toxic goiter when our dosimetric approach was applied.

"False-positive" myocardial perfusion scintigraphy findings in patients with angiographically normal coronary arteries: insights from intravascular sonography studies.

UNLABELLED: Abnormal exercise perfusion findings have been described as false-positive for coronary artery disease in patients with suspected angina and angiographically normal coronary arteries. METHODS: The significance of this finding was further investigated by obtaining intravascular sonograms and Doppler guidewire measurements of at least 2 coronary arteries in 20 consecutive patients who had chest pain, normal coronary angiography findings, and positive stress-rest sestamibi SPECT findings. The summed reversible score was used to describe the extent and severity of reversible perfusion defects. On the basis of scintigraphy findings, vessels were grouped as supplying underperfused myocardial segments (target vessels, n = 20) or normal territories (reference vessels, n = 25). The presence and extension of atherosclerotic disease of the epicardial arteries were assessed by intracoronary sonography. Measurements of plaque area (PA), vessel area (VA), and relative cross-sectional PA (RPA) (RPA = PA/VA) were obtained at the site of maximum plaque concentration. The coronary flow velocity reserve (CFR) was assessed during adenosine-induced hyperemia, and the relative flow reserve was calculated as the target-to-reference coronary reserve ratio. RESULTS: The median summed reversible score was 3 (range, 1-6). Intracoronary sonography showed occult atherosclerosis in 19 patients (95%), with RPA greater than 40% in 16 patients (80%). Mean RPA was significantly greater in the target vessels (46% +/- 14%) than in reference vessels (12% +/- 18%; P < 0.0001). Doppler flow velocity measurements showed abnormal vasodilation capacity (CFR < 2.5) in 14 patients (70%). Mean CFR was significantly lower in the target vessels than in the reference vessels (2.3 +/- 0.5 versus 3.1 +/- 0.6; P < 0.0001). A significant inverse correlation was seen between the summed reversible score and the coronary reserve ratio (y = 9.05x - 9.9; r = 0.70; P < 0.005). CONCLUSION: Reversible perfusion defects seen on SPECT images are often associated with angiographically unrecognized occult atherosclerotic changes and an abnormal vasodilation capacity of the coronary circulation. The tendency to dismiss abnormal exercise perfusion findings as false-positive in these patients may be unjustified.

Diagnostic criteria for detection of postinfarction ischemia by quantitative analysis of stepwise dobutamine radionuclide ventriculography.

BACKGROUND: Application of the traditional diagnostic criteria validated for exercise testing may be inappropriate when dobutamine infusion is associated with radionuclide ventriculography (RNV). The objective of this study was to establish appropriate diagnostic criteria for evaluation of dobutamine stress testing with RNV for the detection of early postinfarction ischemia. METHODS: RNV was performed at baseline and during dobutamine infusion in 10 control subjects and in 30 patients who were studied within 1 week after uncomplicated myocardial infarction. Several quantitative parameters including left ventricular ejection fraction (EF), regional EF, and absolute change in global and regional EF were tested. In addition, regional wall-motion changes were scored by visual analysis. The limit of normal response for each quantitative parameter was defined as the 95th percentile of the distribution observed in control subjects. On the basis of predischarge clinical evaluation and exercise stress testing, patients were grouped as having evidence of residual ischemia (group 1, 15 patients) or no evidence of ischemia (group 2, 15 patients). Sensitivity, specificity, and accuracy in the detection of postinfarction ischemia were calculated for each parameter, and empiric receiver-operating characteristic curves were generated. RESULTS: The limits of the normal response to dobutamine infusion in the control subjects were found to be a 7.5% and a 12.5% increase in global EF at low and high dose, respectively. Median baseline EF was significantly lower in patients than in control subjects (Mann-Whitney U test: P < .001). There were no differences in resting EF between group 1 and group 2 patients. However, median high-dose EF and increase in EF were significantly lower in group 1 as compared with group 2 patients (56% vs 72% and 5% vs 17%, respectively; Mann-Whitney U test: P < .0001 for both). A biphasic (up-and-down) response with initial increase at low dose followed by decrease or no change in EF at high dose was observed in 66% of group 1 patients and only in 13% of group 2 subjects. The best criterion for detection of postinfarction ischemia was a change of <12.5% in global EF at high-dose dobutamine infusion, with 80% predictive accuracy. The traditional criterion, a change of <5 % or a decrease in EF, yielded an accuracy of only 63%. The association of a change of <12.5% with a biphasic response increased accuracy to 87%, with a sensitivity of 93% and a specificity of 80%. Quantitative regional wall motion analysis showed greater diagnostic accuracy than visual wall motion scoring (83% vs 70%). CONCLUSIONS: Application of appropriate criteria and stepwise quantitative analysis of RNV during dobutamine infusion may increase accuracy in the detection of early postinfarction ischemia.

Chromogranin-A as a serum marker for neuroendocrine tumors: comparison with neuron-specific enolase and correlation with immunohistochemical findings.

BACKGROUND: Chromogranin-A (Cg-A) is a 439-amino-acid protein contained in secretory granules of neuroendocrine cells, in addition to specific hormone peptides or neuropeptides. Since Cg-A is co-released with peptide hormones its serum concentration can be used as a marker of neuroendocrine tumors. AIM: Evaluation of the analytical performance of a new IRMA method for Cg-A assay and of the clinical value of serum Cg-A and neuron-specific enolase (NSE) in neuroendocrine tumors. In addition, we compared the diagnostic usefulness of both Cg-A and NSE serum levels and their relationship to tissue expression. PATIENTS AND METHODS: Initially we evaluated the analytical performance (intra- and interassay imprecision, dilution test and detection limit) of the Cg-A RIACT method (CIS Bio-International, Gif-sur-Yvette, France). We selected 50 patients affected by various histologically confirmed neuroendocrine tumors (NETs): 111In-pentetreotide scan and helical computed tomography were employed to assess tumor extent. Cg-A and NSE were measured before surgery in serum samples of patients and 50 age-matched controls by IRMA methods. After surgery immunohistochemical stains for Cg-A and NSE were performed on surgical specimens of tumor tissue. RESULTS: Cg-A levels were significantly higher (p < 0.0001) in patients with NETs than in healthy controls and we found a positive correlation between serum and tissue expression (p < 0.05). Serum levels of Cg-A were also related to tumor extent (p < 0.05) but in some cases we observed significant elevation of serum Cg-A in small, intensely immunoreactive NETs. ROC curve analysis showed better accuracy for serum Cg-A compared to NSE in the diagnosis of NETs, while no significant relationship was found between serum expression and immunostaining for NSE. DISCUSSION: Our results confirmed the biological and clinical significance of circulating Cg-A as an expression of granular content in neuroendocrine tissues and supported the complementary usefulness of serum Cg-A in the diagnosis and evaluation of NETs together with imaging modalities.

Uptake of In-111 pentetreotide by normally functioning nodular goiters.

After the intravenous administration of a radiolabeled somatostatin analogue (octreotide), normal thyroid and neoplastic and nonneoplastic thyroid lesions can be visualized. The authors present the cases of two patients who underwent somatostatin receptor scintigraphy (SSRS) using In-111 pentetreotide: one for the study of suspected paraneoplastic ACTH hypersecretion, and the other for a restaging of breast carcinoma with neuroendocrine features. In both patients, SSRS revealed increased uptake in the thyroid, corresponding to "cold" nodules on Tc-99m pertechnetate imaging. Cytologic and histologic examinations showed the typical features of thyroid goiters without lymphocytic infiltration.

Effective radiation dose to the patient and to the general population from nuclear medicine procedures: variations in the last twenty-year period.

We have evaluated how changes in nuclear medicine (NM) techniques over the last twenty-year period have modified radiation exposure to the patient and population. For this purpose, we estimated the variations in the mean effective dose to the patient, and both the collective and the per capita effective dose to the population of the province of Varese, derived from radioisotope examinations carried out in the four NM Centers of this province in the years 1972, 1981, and 1991. Dosimetric calculations were based on ICRP Publication 53 for most of the radiopharmaceuticals used, and tissue weighting factors were based on ICRP Publication 60. The total number of NM exams carried out was 19,744 in 1972, 31,973 in 1981, and 23,623 in 1991. Between 1972 and 1991 there has been a substantial decrease in the effective irradiation to the patient and to the general population (mean effective dose to the patient: from 21.2 to 6 mSv; per capita mean effective dose: from 0.58 to 0.18 mSv), and in the per capita equivalent dose to some target organs, such as the thyroid (9.6-->1.5 mSv) and liver (0.51-->0.07 mSv). At the same time, there has been a significant increase in the per capita equivalent dose to the bladder (0.05-->0.48 mSv), skeleton (0.08-->0.36 mSv), and testes (0.02-->0.15 mSv), and a less marked increase to the ovaries (0.03-->0.06 mSv). The per capita equivalent dose to red marrow (0.13-->0.1 mSv) and to the large intestine (0.1-->0.12 mSv) did not change significantly.

Performance evaluation of a hand-held gamma detector probe used for radioimmunoguided surgery.

The success of radioimmunoguided surgery (RIGS) is dependent on the performance parameters of the apparatus, its correct handling, and the employment of a suitable radioactive compound. In the present study the authors examined the performance of the Neoprobe 1000 device with respect to the radioisotope 99mTc. Detecting efficiency was evaluated experimentally using a phantom containing a radioactive point source which could be moved both vertically and horizontally with respect to the central axis of the probe. In this way curves representing the variations in efficiency as a function of the vertical and horizontal distances of the source from the probe were constructed. Furthermore, values of minimum detectable activity as a function of source depth, counting time and background radioactivity were calculated. These results were compared to those previously obtained using 125I, the radioisotope most frequently employed in RIGS. The graphs and tables included could serve as a practical aid to help the operator obtain the best possible measuring conditions, thereby maximizing his/her results.

[Study of intestinal absorption of calcium using 47Ca and whole body counter in renal calculosis with hypercalciuria]. / Studio dell'assorbimento intestinale del calcio mediante 47Ca e misure con whole body counter nella calcolosi renale con ipercalciuria.

Intestinal calcium absorption was studied using orally administered 47Ca and whole body counting. Using this method, we examined 82 patients suffering from recurrent calcium urolithiasis associated with idiopathic hypercalciuria, to evaluate the incidence of elevated intestinal absorption of this ion. An oral dose of 111 kBq (3 microCi) of 47Ca chloride, together with 250 mg of stable calcium as carrier, was given to each patient. Two hours and one week later, the total body radioactivity of each subject was measured. The retention of 47Ca, as percentage of the administered dose, was then calculated. The measurements were performed with a whole body counter consisting of a two-crystal moving system with shadow shield. Forty age-matched healthy volunteers were also examined. The whole body retention of 47Ca resulted significantly higher (p less than 0.0002) in the group of patients than in the control sample, whose m +/- SD was 22.0 +/- 6.0%. In particular, by defining the normality range as 10-34% (m +/- 2SD of control results), enhanced intestinal absorption of calcium was found in 28% of the examined patients. The use of this simple examination seems to be helpful in the physiopathologic assessment of subjects suffering from calcium urolithiasis and idiopathic hypercalciuria and consequently, in their appropriate management.

Intestinal calcium absorption in rheumatoid arthritis. A study using whole body counting.

Conflicting results are reported in the literature concerning the changes in intestinal calcium absorption in rheumatoid arthritis (RA). In the present work, intestinal calcium absorption was studied in 27 postmenopausal women with RA, using whole body counting as the study method and orally administered Ca-47 as the tracer. Nobody was on corticosteroid therapy, but all received non-steroidal anti-inflammatory drugs and hydroxy chloroquine or gold compounds. The mean calcium absorption was 22.3% of the dose administered, with a standard deviation of 8.0%. The results obtained were not significantly different from those of 40 age- and sex-matched controls (mean +/- SD: 22.0% +/- 6.0%). Our findings seem to exclude the hypothesis of calcium malabsorption as one of the causes leading to osteoporosis in RA.

[Phase and amplitude images using Fourier analysis in radioisotopic angiography. Comparison with contrast angiography for studying regional changes in ventricular contraction]. / Immagini di fase e ampiezza mediante analisi di Fourier in angiografia radioisotopica. Confronto con l'angiografia di contrasto per lo studio delle alterazioni regionali della contrazione ventricolare.

Phase-amplitude images and phase distribution histograms, derived from a temporal Fourier analysis of equilibrium ecg-gated blood pool studies, were used to assess the overall wall motion synchronism and to detect regional wall motion abnormalities in 69 consecutive patients with suspected or documented coronary artery disease, in whom biplane contrast left ventriculography and coronary angiography were performed. Four regions were considered on the 15 degrees caudal left-anterior oblique view radionuclide image, in order to identify the 7 conventional angiographic left ventricular wall segments (as the American Heart Association Council of Cardiovascular Surgery). Regional abnormalities on the phase-amplitude images from the 15 degrees caudal left anterior oblique view scans were studied in order to identify local hypokinesis, akinesis or dyskinesis (in accord to definitions used for contrast cineangiography) relative to seven conventional left ventricular wall segments. Results of phase-amplitude image analysis were compared with those of contrast cineangiography. The parametric images showed overall sensitivity of 82% and 92% respectively towards biplane and monoplane (left anterior oblique) contrast cineangiography, with a high degree of specificity (97%). Most akinetic and dyskinetic segments were correctly identified. A significant phase delay (greater than or equal to 70 degrees) from mean value, always occurred in dyskinetic segments and generally related to the severity of the wall motion abnormality. Lower accuracy was observed for hypokinetic regions; sensitivity was lower for apical and antero-lateral segments.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcitonin in chronic renal failure.

The pattern of circulating calcitonin (CT) has been studied in relation to other humoral factors (PTH, calcium, phosphate and magnesium) in patients with chronic renal failure on either conservative or dialysis treatment. The latter group was studied before and after dialysis. In both groups, in basal conditions there was a significant increase in the circulating levels of CT, PTH, phosphate and magnesium and a significant decrease in calcemia compared to control group values. Positive correlations were found between increased CT and PTH and between CT and phosphate in uremic patients on conservative medical treatment, but not in those on hemodialysis. In the hemodialyzed group, the postdialysis increase in calcemia was significantly correlated to an increase in calcitoninemia. These data would indicate that even in severe uremia parafollicular cells are still able to increase CT secretion in response to physiological stimuli.